Hey guys. I did a search but I didn't come up with anything. My 02L has a surging problem on acceleration. If I start out from a dead stop in first gear the truck pulls hard and accelerates smoothly. If I get on it in 3rd gear and it downshifts to second, I feel a surging during acceleration and I can hear the blower whine change pitch with the surge. I only notice the surge under boost conditions in 2nd and 3rd gear. It's like the belt on the blower is slipping but why would it just do it under load in 2nd gear? It has 14,000 miles idles smothly and I'm running the stock plugs.

My only mods right now are a K&N panel filter and a Bassani catback. It had this problem before the Bassani but it's just now really starting to bug me. I have a brand new fuel filter and I cleaned the IAC and mass air meter 2 weeks ago. I reset my TPS voltage to .992 and my blower belt looks good and it is very tight.
Could it be my converter locking and unlocking? Any other ideas?

Thanks,

Randall

 

That would be the torque reduction.

 

I thought the torque reduction kicked in between shifts?

I feel can feel and hear the surge starting at about 3000 rpm and it does it until it shifts at 5000.

 

I don't believe you are experiancing torque reduction. TR usually only happens under full throttle, sounds like farting when it shifts from 1-2 especially. What you describe is the TC locking up. Fords are like this. RPM's will hold or slightly drop but speed will continue to build.

 

So the torque converter will lock and unlock as your speed builds? When I say surging, I mean it does it 4-5 times through the RPM range I described above. It's like I am pressing and releasing the gas pedal slightly but I'm not.

Sorry, it's hard to explain.

 

Belt slip.

Change your belt, or check your set up. Better yet watch the boost guage while accelerating.

Mine does the same thing when the belt is wearing out. The reason it slips on the downshift is the rapid change in RPM's.